The Liquid Crystalline Blue Phases (LC BPs) and their diffraction patterns were investigated experimentally and theoretically. We stabilized Blue Phases and measured their diffraction pattern for different wavelengths of monochromatic light with the help of a conoscopic setup of a polarization microscope. Moreover, the diffraction patterns were calculated with the help of a 4x4 matrix method which allows amplitude and phase investigations.
The simulation of polymer-dispersed cholesteric liquid crystals is carried out using a model, which takes into account the domain structure of the layer. The model is based on the 4x4 matrix calculation method of Berreman. One considers different orientations of the helical axis in multi- and single-domain configurations. The distribution of the helical axis orientations in the multi-domain model allows the description of optical properties of multi-stable director configurations.